What is the right way to append entity from one manager to another in breeze?

问题

What is the right way to append entity from one manager to another? Straight forward attempts result in overwriting entities or in warning about the same entity key...

var entity = em1.getEntities()[0];
em1.deattachEntity(entity);

// assume em2 already has entities
em2.attachEntity(entity);

I believe there should be some in-build functionality for appending entries to another non empty manager or for generating an unique key for selected manager.

Any suggestions?

UPDATE:
I did read the documentation and tried to do it via exportEntities and exportEntities:

    var entity = em1.getEntities()[0];
    var export = em1.exportEntities([entity], false);
//here em2 already has entity with the same key as entity that I want to add
    var import = em2.importEntities(export, { mergeStrategy: breeze.MergeStrategy.Disallowed });

This gives me an error: A MergeStrategy of 'Disallowed' prevents Picture:#Macaw.Whitelabel.WebAPI.Models--1 from being merged

I really don't understand how to append entities....

UPDATE2: I did discover that manually assigning id of the attached entity solves the problem and error disappears. Is there a way to make it not manually but using breeze?

来源：https://stackoverflow.com/questions/23914060/what-is-the-right-way-to-append-entity-from-one-manager-to-another-in-breeze